OBJECTIVES: The studies on cellular membranes in Duchenne Muscular Dystrophy are to include: (1) Studies on red blood cell permeability under conditions of various means of applied stress. (2) Development of accurate methods for serum creatine phosphokinase isoenzyme distribution analysis and erythrocyte adenylate kinase isoenzyme analysis in dystrophics and female carriers. (3) Continued studies on the physical chemical properties of normal and dystrophic creatine phosphokinase isoenzymes and of the adenylate kinase isoenzymes to determine whether there are any degrees of specificity associated with their unusual cellular permeability in Duchenne dystrophics. (4) Continued electron spin resonance studies on the abnormal cell membrane of the dystrophic and female carrier, and also on the diseased sarcolemma during early phases of the pathogenesis. (5) Final studies will then center on female carrier detection and genetic studies to test the mutation hypothesis for the occurrence of sporadic cases and to compare it with alternative mechanisms.